Valve



UNITED STATES PATENT OFFICE.

WESTON M. FULTON, OF KNOXVILLE, TENNESSEE, ASSIGNOR TO THE FULTON GOM- PANY, OF KNOXVILLE, TENNESSEE, A CORPORATION uF MAINE.

VALVE.

Specification of Letters Patent.

Patented Mar. 8, 1921.

Original application filed April 20, 1914, Serial No. 833,237. Patent No. 1,176,535, dated March 21, 1916. Divided and this application filed March 3, 1916, Serial No. 81,912. Renewed January 19, 1921.

Serial No. 438,530.

To all whom it may concern:

Be it known that I, \VEsToN M. FULTON, a citizen of the United States of America, and a resident of Knoxville, Tennessee, have invented a new and useful Improvement in Valves, which invention is fully set forth in the following specification.

This invention relates to self-acting valves, and more particularly to valves of this class in which the operation of the valve is controlled by a pilot valve, operated by hand or by automatic control means.

In valves of this type, there is provided a casing separated into a high pressure receiving side and a low pressure delivery side communicating with each other through an opening controlled by a valve usually operated by a piston the movement of which is controlled by a pilot valve operated by more ,or less delicate outside means, such as centrifugal governors, timing apparatus, thermostatically controlled elements, lOW pressure systems, magnetic devices op erating from a distance, etc. Owingto the difliculties experienced in making the piston fluid-tight, leakage often occurs around the piston, thereby resulting oftentimes in the unexpected operation of the valve. While attempts have been made to compensate for this leakage by use of a large pilot valve, it is found that the leakage defect is usually progressive while the provision for caring for it remains constant, with the result that the leakage difliculties continue; furthermore, the. larger the pilot valve the more work is thrown on the device which operates this valve, thereby reducing the sensitiveness of the device.

With the object of overcoming the above objections, my invention resides in providing in a self-operated pilot-controlled valve, such as used for reducing from high to low pressure, a collapsible and expansible corrugated vessel having an operating connection with the valve member on the low pressure side of the valve and being in communication with the high pressure side through a conduit controlled by a pilot valve. The valve is moved into opening position against tension, such as afforded by a spring, when high pressure fluid is permitted, by the pilot valve, to accumulatein the vessel and is moved into Pl \sing position, when the vessel The use of my collapsible and expansible vessel in the manner described avoids leakage past a piston and reduces this loss to merely that required for lowering the pressure in the vessel to that of the atmosphere, or that in the low pressure system. The construction permits a very small pilot valve to be used, thereby reducing the power to operate it and consequently increasing the sensitiveness of control.

The present ap lication is a division of my application erial No. 833,237, filed April 20, 1914, which has matured into U. S. Patent No. 1,176,535 of March 21, 1916, wherein the present invention is described but not specifically claimed.

The collapsible and expansible metal vessel which I prefer to employ consists of a flexible corrugated sheet metal wall of the character shown and described in my U. S. Patents Nos. 887,084, 903,465, 947,229, 967,010, 975,519, 976,060 and 979,460, having one end stationary and secured to the wall of the valve casing, the opposite movable end being closed by an inflexible end wall which is connected with the valve to be operated.

Referring to the drawing, which presents a vertical longitudinal section of a valve embodying my invention, 34 is a valve casing preferably having a flanged inlet 35 and a flanged outlet 36 for connecting with a pipe line. A partition 37 separates the valve casing into high and low pressure compartments, respectively, and has an opening in which is secured a valve seat 38. The casing is provided with an enlargement 39 on the low pressure side of the partition 37 for receiving a collapsible and expansible vessel 40, preferably of the kind described in my patents above referred to. The upper end of the vessel is provided with a flange 41 for supporting it on the flanged edge of the casing wall 39 and is held in place under a washer 42 by a closure 43 adapted to be bolted or otherwlse secured to the casing. The lower end of vessel 40 is closed by an inflexible wall 44 to which is secured a valve stem 45v carrying a valve 46 adapted to engage the seat 38 and which is pressed toward seating position by a spring 47 resting at its lower end in a cup '48 formed on the inner side of a cap 49 which has a socket 50 for guiding the lower reduced end of the valve stem 45. The casing closure 43 is provided with a chamber 51,

the upper end of which is adapted to be closed by the threaded extension 52 of a pilot-valve casing 53. In't-he body of closure 43 is drilled a passage 54 closed at its outer end by a plug 55 and opening into chamber 51 at the opposite end. This passage has a side opening 56 adapted to register with a passage 57 in the wall of the main casing 34, thus providing open communication between the high pressure part. of the line and chamber 51. In the pilotvalve casing 53 is provided a chamber 58 which is adapted to communicate with chamber 51 through a valve-controlled port 59 formed in a screw-plug-60. This passage is controlled by a pilot-valve 61 which is carried at the end of a hollow stem 62 passing through a packing joint 63 of usual construction. The valve stem 62 has a side duct 64 which permits communication between chamber 58 and a place of'lower pressure, such as the atmosphere, when the stem is lowered by means such as a thermostat or other suitable operating device. Communication is established between chamber 58 and the interior of the collapsible and expansible vessel through a passage 65 in the wall of casing 53 and a registering passage 66. A tight joint is provided between parts 53 and 43 by packing 67. 71 is a portion of a frame which may be secured to the casingfor supporting any suitable means for actuating the pilot-valve stem 62.

without detailed explanation. With the parts in the position shown, the interior of the collapsible and expan'sible vessel communicates with the high pressure system through a pilot-valve controlled port 59, and under this pressure the vessel extends against the action of spring 47 and against the low pressure on the exterior of the vessel. Valve. 46 under these conditions is held in open position. Whenvalve stem 62 is lowered by operation of a thermostat or other operating device, passage 59 is closed and the collapsiblev and expansible vessel 40 is vented to the atmosphere or other place of lower pressure through duct 64 and the passage in the valve stem. Spring 47 and the low pressure of the line now are permitted to become effective to lift the valve 46 to seating position where it is held by the spring and the high pressure in the line until again opened by operation of the pilot-valve.

From the above, it will be seen that the use of a sliding piston in the type of valve described is obviated, together with its leakage difficulties, and that the small size of opening in the pilot-valve makes it possible to use very delicate operating means for tion and the interior of said vessel, a rectilineally-movable pilot-valve controlling said passage, and a passage in the stem of said pilot-valveadapted to be brought into communication with the interior of said vessel when said pilot-valve is moved longi- From the above description, the operation of the device will be readily understoodv tudinally to close said first passage.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

WESTON M. FULTON. Witnesses I. A. MARTIN, J. V. Grnsnsn. 

